Please see the relevant ticket in the Planetary Developers Forum, namely http://trac.mathweb.org/planetary/ticket/253.  This ticket makes note of an earlier proposal about content sharing between PlanetMath and P2PU.  A spin off of that proposal was a more general discussion about generic content sharing, relevant to the furtherance of P2PU's mission.

The Planetary folks presumably won't have time to move on integrating math support into Lernanta until after August, when both Planetary and Lernanta will be more stable.  For the moment, this can be a place to talk about what "math support" means to you.